Flight attendants and pilots had the highest and second-highest risk-adjusted percentages of deaths from radiation-related cancers, respectively, among more than 500 occupations in the United States, according to the results of a population-based analysis reported by Patel et al in a research letter published in JAMA Internal Medicine.
Study Details
Investigators used National Vital Statistics System data from U.S. death certificates between 2020 and 2024 that were linked to decedents’ usual occupations. The analysis evaluated mortality from cancers classified as radiation-related—including breast, central nervous system, multiple myeloma, leukemia other than chronic lymphocytic leukemia, lymphoma, thyroid, prostate, melanoma, and nonmelanoma skin cancers—as well as mortality from non–radiation-related cancers. Lung cancer was excluded to reduce potential confounding related to smoking.
Nuclear technologists, who have occupational exposure to ionizing radiation from noncosmic sources, served as a positive control group. Aircraft assemblers and aircraft mechanics served as negative controls because they work around aircraft but do not experience sustained in-flight cosmic radiation exposure.
Using multivariable logistic regression, the investigators calculated odds ratios (ORs) for cancer mortality by occupation, adjusting for age at death, sex, race, ethnicity, educational level, and marital status.
Key Results
The analysis included 12,710,517 decedents across 503 occupations, including 14,190 pilots (97.3% of whom were males) and 7,170 flight attendants (84.3% females). Flight attendants had the highest risk-adjusted percentage of deaths from radiation-related cancers, at 6.9% (95% confidence interval [CI] = 6.4%–7.5%), followed by pilots at 6.7% (95% CI = 6.3%–7.1%). In contrast, aircrew ranked near the median of occupations for deaths from non–radiation-related cancers. Aircraft mechanics and assemblers did not demonstrate elevated radiation-related cancer mortality, while nuclear technologists had the 12th-highest percentage.
The risk-adjusted odds of radiation-related cancer mortality were higher among pilots (OR = 1.36, 95% CI = 1.28–1.45) and flight attendants (OR = 1.50, 95% CI = 1.38–1.63) compared with all other occupations. Significant elevations were observed in both groups for breast, central nervous system, prostate, and melanoma mortality. For example, breast cancer mortality ORs were 1.57 (95% CI = 1.09–2.26) for pilots and 1.61 (95% CI = 1.44–1.81) for flight attendants; prostate cancer mortality ORs were 1.38 (95% CI = 1.26–1.51) and 1.75 (95% CI = 1.22–2.51), respectively. Leukemia mortality was also significantly elevated among pilots (OR = 1.27, 95% CI = 1.08–1.49).
“These findings support consideration of occupational radiation protections for aircrew members commensurate with their exposure level,” the authors concluded.
Anupam B. Jena, MD, PhD, of the Department of Health Care Policy, Harvard Medical School, Boston, is the corresponding author for the JAMA Internal Medicine article.
DISCLOSURE: For full disclosures of the study authors, visit jamanetwork.com.
